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Subject: Re: [boost] Review manager for Boost QVM?
From: Emil Dotchevski (emildotchevski_at_[hidden])
Date: 2014-06-06 18:16:59

On Fri, Jun 6, 2014 at 1:39 PM, Peter Dimov <lists_at_[hidden]> wrote:
> Emil Dotchevski wrote:
>> If a matrix type stores its values as anything but a 1-dimensional array
>> in column-major order, you can't (portably) feed it into glUniformMatrix4fv
>> without a temporary; at least it'd require a cast, which in theory may not
>> work on some platform.
> Actually, a two-dimensional array is guaranteed to be laid out linearly in
> memory. The rest of the message still stands though.

You need a cast, and my understanding is that that makes your code not
portable because it violates the strict aliasing rule. This is purely
theoretical, obviously, in practice it'll most likely work.

Anyway, if you want to use a 2D array and cast it to 1D array, there
is nothing in the QVM library that would get in your way.

Emil Dotchevski
Reverge Studios, Inc.

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